Fabrics 9 are generally made from fibers, and are roughly classified into a woven fabric 91 (see FIG. 1) and a knitted fabric 92 (see FIG. 2). The woven fabric 91 is made by the interlacement of warp threads 911 running parallel lengthwise and weft threads 912 running parallel crosswise. The knitted fabric 92 is made by creating consecutive rows of interlocking loops 920 of thread 921 using needles, thereby making the knitted fabric. The knitted fabric 92 is more stretchable and loose than the woven fabric 91.
A coating material may be applied to the fabric 9 to form a coating layer on the fabric 9. The coating layer may be subjected to wet-solidification or dry-solidification to provide the fabric 9 with a functional layer having water-proof and breathable functions.
With reference to FIG. 3, since the woven fabric 92 is relatively tight and less stretchable, it may be coated with a coating material 3 using a roller coating machine 8 in which the woven fabric 91 is conveyed by rollers 81 so that a uniform coating layer 31 can be formed on the woven fabric 91. However, if the coating material 3 is applied to the knitted fabric 92 using the roller coating machine 8, since the knitted fabric 92 is more stretchable than to the woven fabric 91, as mentioned above, it will be stretched by the rollers 81 so that the coating layer 31 which is applied to the knitted fabric 92 in a uniform manner becomes deformed and is uneven in thickness when the stretched knitted fabric 92 is removed from the rollers 81 and returns to its normal state (i.e., an unstretched state). In addition, the knitted fabric 92 may sag under the weight of the coating material 3 since the knitted fabric 92 has a relatively loose structure, thereby causing the coating layer 31 formed thereon to be uneven. Alternatively, when the coating material 3 is applied to the knitted fabric 92 manually using a doctor blade, the knitted fabric 92 may deform due to stretching caused by the doctor blade in contact therewith, which may also make the coating layer 31 uneven.
With reference to FIG. 4, to overcome the aforesaid problems, there has been developed a method for applying a coating layer to the knitted fabric 92, in which a coating material 41 is applied evenly to a releasing paper 6, followed by dry-solidifying to form a uniform solid coating layer 42 on the releasing paper 6. A binder 5 is applied to the knitted fabric 92 to form a binder layer 51, followed by bonding the uniform solid coating layer 42 together with the releasing paper 6 to the binder layer 51 on the knitted fabric 92. The knitted fabric 92 provided with the uniform solid coating layer 42 as a functional layer is obtained by removing the releasing paper 6 from the uniform solid coating layer 42 after the binder layer 51 is solidified.
Although the knitted fabric 92 can be provided with the uniform solid coating layer 42 using the aforesaid method, the binder 51 sandwiched therebetween may negatively affect the function such as water-proof and breathable functions, of the uniform solid coating layer 42 imparted to the knitted fabric 92. In addition, since the releasing paper 6 has a low structural strength, it is liable to breaking under high tension during the application of the coating material 41 to the releasing paper 6 conveyed by the rollers 81 of the roller coating machine 8. Furthermore, as the structural integrity of the releasing paper 6 may be negatively affected after absorption of water, the wet-solidifying process is not suitable for solidifying the coating material 41 applied on the releasing paper 6 to form the uniform solid coating layer 42.
In a co-pending application of the present assignee, Ser. No. 14/332188 (Publication No. US20160017527), filed Jul. 15, 2014, a method for coating a knitted fabric is disclosed. The method includes the following steps of: attaching a knitted fabric flatly onto a carrier sheet to form a laminate, the carrier sheet having a tensile strength greater than that of the knitted fabric; forming a coating layer onto a top surface of the knitted fabric; and separating the knitted fabric with the coating layer from the carrier sheet.